Method and means for forming paper cups



March 18; 1941. w AMBERG j I 2,235,348

METHOD AND MEANS FOR FORMING PAPER CUPS I Filed Jan. 9, 1939 ATTORNEY.

Patented- Mar. 18, 1941 UNITED STATES PATENT OFFICE METHOD AND MEANS FgR'FORMING PAPER Walter E. Amber Chicago, 111., assignor to Universal Paper Products Company, Chicago, 11]., a

corporation of Illinois Application January 9, 1939, Serial No. 249,859

7 Claims.

In the manufacture of cone-shaped paper cups of the general type described in my United States Patent No. 2,056,893, by the general methods described in my United States Patents Nos. 2,139,-

613 and 2,139,614, particularly where the cup is formed with a. pocket of material at the apex,

I have found that some difficulty may be experienced in properly forming the apex. This difficulrty is apparently due to the fact that the material around the apex as it is being wound into a cup tends to become folded or crushed inwardly in a manner such as to interfere with the leak-proof formation of the tip of the apex. This tendency of the material to fold in the wrong direction is almost imperceptible and can hardly be detected with the naked eye, but nevertheless, will occur again and again in the formation of cone-shaped paper cups on continuous 2 operating machines.

One of the objects of the present invention is to provide a method and means for overcomin v the aforementioned dimculties and thereby to bring about the uninterrupted formation of coneshaped cups of .the type described on continuous machines.

Another object is to provide a new and im-v proved method and means for properly sealin the apex of cone-shaped cups or other receptacles in order to render them leak-proof. Other objects will appear hereinafter.

I'he invention comprises the application of a predetermined pressure and preferablythe formation of a predetermined crease at the point of the paper or other material whichlis to form the apex of the cone-shaped receptacle. In practicing the invention, a predetermined crease may be formed in the paper or other material prior to the time that it is wound into a cup, or the predetermined pressure may be applied or the crease may be formed at the point which is to form the apex while the material is being wound into a cup or contemporaneously with the winding operation. Many different types of operations may be employed in order to apply a predetermined pressure at the point of the material which is to form'the apex ,or in order to form a predetermined crease. In general, these operations are simple but highly effective.

55, The details and further features of the invention will become apparent from a reading of the following specification in the light of the accompanying drawing, in which:

Figure 1 represents a form of blank which may be used in making paper cups and which is I particularly adapted for the making of paper cups by the present invention; s

Figure 2 represents another form of blank particularly .adapted for making paper cups while utilizing the principles of this invention; 10'

Figure 3 represents one modification of the invention in which a predetermined crease is 1 formed in the material by crimping or scoring rolls disposed on opposite sides of the material;

Figure 4 represents another modiflcationof 15 the invention by which the paper or other material is crimped or creased by the operation of a scoring point or finger against a suitable support with the paper disposed intermediately in between;

Figure 5 represents a mechanism for applying a predetermined pressure and for forming a predetermined crease during the winding or forming'operation of a cone-shaped cup;

Figure 6 is a plan view with parts broken away 25 of the apparatus illustrated in Figure 5;

Figure 7 illustrates another means for applying a predetermined pressure exactly at the point or apex oLthe cup while it is being formed;

Figure 8 is intended to illustrate the nature of 30 the fold' desired in carryin out this invention as contrasted with the fold which may occur otherwise;

Figure 9 illustrates another modification of the invention by means of which a properly 3: shaped hood is held over the paper during the forming "operation until a crease is formed;

Figure 10 illustrates anothermeans for applying a predetermined pressure at the apex of the cupduringthe forming operation with fluid 4o pressure and vacuum.

Referring to Figure 1, the cup blank A comprises opposite parallel straight sides 2 and 4 and opposite curved sides 6 and 8 having the crease terminating at center point I. Blanks of this type may be cut from a strip of paper and formed into cone-shaped paper cups by rolling them around point III as the apex of th cup.

The formation ofa cup may be accomplished as described in my United States Patents Nos. 2,139,613 and 2,139,614 by rolling the material constituting blank A around a conical former having its apex substantially at point III. This former may roll in an orbit against an immobile supporting surface, with blank A between the said surface and the former in such a manner that as the former rolls in a counter-clockwise direction it picks up the edge of a strip of paper at point 16 and begins to form it-into a cone. As the formation of the cone continues, the paper is severed from a continuous strip along side 6 by means of cooperating knives between the cone and the supporting surface. In accordance with this invention, in order to facilitate the formation of a cup, the creases I2 and I4 are formed, as hereinafter more fully described, either prior to or during the winding operation.

In Figure 2, a blank B is severed from the end of a continuous strip along lines of equal radii l8 and 20, the center of convex side 20 being at point 22. Point 22 is likewise the point at which the apex of the cone is formed. As in the case of blank A, predetermined crease lines 24 and 26 are formed prior to or during the winding op-' eration by which blank B is wound around a conical mandrel into a cone-shaped cup.

It will be observed that creases I 2 and [4 of blank A and creases 24 and 26 of blank'B are both made up of a short crease and a long crease. Further, it will be noted that these creases are in opposite directions. For example, the edges of the long creases I4 and 26 of blanks A and B, respectively, are up, while the edges of the short creases I 2 and 24, respectively, are down, looking at the blanks as they appear in the drawing.

It will be further understood that blanks A and B are not necessarily formed as such, and, in fact, according to one method of making paper cups as described in United States Patent No. 2,139,614, are not blanks at all until after the cup is formed, but rather-are portions of a continuous strip of material which is unwoun from a roll.

According to the modification of the invention shown in Figures 3 and 4, this continuous 'strip ofmaterial is crimpedor creased ahead of time, that is, ahead of the winding and severing operation, either by means of scoring rolls 28 and 30 provided with scoring projections 32 and 34 in the form of teeth as illustrated in Figure 3, or by means of a stamp 36 adapted to move up and down against.the paper, while the latter is passing over a supporting surface 34, as illustrated in Figure 4. In this case, a crease is formed by a projecting point 40, which is so arranged to score the paper without tearing it. In either of the cases illustrated in Figure 4, creases may be formed along lines similar to lines l2 and I4, as shown in Figure 1, or lines '24 and 28 as shown in Figure 2, so that in the subsequent winding operation, the natural inclination of the pa- Per will be to follow the lines which have been weakened by scoring. It will beunderstood that the crimping rolls in Figure 3 are adapted to move toward and away from a continuous strip of paper, and the same is trueof the creasing arm 36, illustrated in Figure 4. The various types of instrumentalities for causing this operation to take place in synchronism with the passage of the paper toward the forming mechanism are not shown, because as will be readily understood, anyone skilled in the art may devise many dif- 2,2ss,a4e

ferent types of mechanism for performing such an operation.

As shown in Figure 5, which represents one of the preferred embodiments of the invention, a. mechanical creaser may be employed to set the crease at the proper point during the cycle of folding the paper into a cone-shaped receptacle. This is illustrated in Figure by mechanical creaser 42, pivoted on pivot 44 and adapted to move toward and away from paper strip 46, as the end of said'strip is being wound upon a conical former 48 and while paper strip 46 is held against a. flat immobile surface 50.

This movement of mechanical creaser 42 occurs approximately at the end of the first revolution of the forming cone, or at that point when the mouth or periphery of the cup is first formed.

This is shown by the plan view of Figure 6. According to the arrangement shown in Figure 6, conical former 48 is moving counter-clockwise around a point 52, which forms the apex of the cone while the paper strip-46 is held against supporting surface 50. At the point illustrated in Figure 6, the mandrel 48 has partially completed the formation of the cup and has partially severed the end of a continuous strip which is moving in the direction of the arrow C. Upon further rotation of mandrel 48, the unsevered portion of the strip, which contains a suitable adhesive, will be securely joined to the already severed portion wound on the mandrel. Before this occurs, however, creaser 42, moving up and down on pivot 44', comes down adjacent the side of mandrel 48 and forms a crease, as generally illustrated bythe dotted lines at point 54. This crease will be in the form generally shown by lines l2 and I4 in Figure 1.

Still another preferred embodiment of this invention is illustrated in Figure I, in which a paper cup is formed from blank B illustrated in Figure 2, and is wound on a conical mandrel which is provided at its apex with a receding plunger or point. As shown, paper 56 is wound on mandrel 58, which contains a passageway 60 and a receding point 62 adapted to recede into passageway 60 at certain intervals during the rotation of mandrel 58, except when it is performing its creasing function. The point or tip 64 of plunger 62 is very sharp and is so designed as to hold the paper of the blank illustrated in Figure 2, for example, exactly at the point 22 which forms the apex. Such a sharp point interferes with the operation of the machine duringthe other stages of the cup-forming operation, as, for instance, when the paper is fed from a continuous roll beneath the conical former. Hence, this point 54 is held in contact with the paper only when the paper is actually being wound into a cup. The use of such a receding point greatly facilitates the formation of a cup, in that it provides the proper formation of pocket 68 as shown in Figure 7.

The purpose of the receding point 54 just described with reference to Figure 7 may be further understood by reference to Figure 8, showing an enlarged view of the crease formed by lines 58 and 10 adjacent the apex I2 of the cup.

In making cone-shaped cup's, I have. found that at the very apex or tip of the cup, so that the pocket 66 of Figure 7 does not lie flat along the wall of the cup. In a number of cases. this improper folding not only affects the appearance of the cup, but tends toprevent it from being leak proof.

, described with reference to Figures and 6, a

hood 82 mounted on a pivot 84 is caused to so over the end of a mandrel and hold the paper in position until a crease 86 is formed.

In Figure 10, the formation .of a predetermined crease is obtained by'the use of, a vacuum applied along a predetermined area through -conduit 88. Instead of employing vacuum, fluid pressure, for example, air pressure or some other force of similar nature can be applied through a predetermined area along-conduit 'fl. can be accomplished in two ways. First, the air can be on continuously and thereby hold the bottom layer of the paper so that the crease forms in theright place, or,'secondly, the air may come on intermittently disregarding the bottom layer of paper and merely 'setting'the' crease in the same way that the mechanical creaser does in Figures 5- and 6. As another modification, fluid pressure can be introduced through conduit 82, at the same time vacuum is,

employed through conduit 80.

In order to facilitate the use of theinvention, the paper or other material may be prepared in various ways to give it temporarily abnormal folding qualities in the areas where pressure is to be applied in order to properly form the apex. Among the methods of treatment which may be employed are the following: (1) the use of moisture; (2) waxing the paper to lubricate the fibers; (3) wet steam applied to the middle of the roll of paper so that the point area alone is softened; (4). an oily spray applied in the point area; and (5) heat applied over the whole area, or over the central portion .of waxed paper to make the wax more fluid so that it may lubricate the fibers better during the creasing period.

It will be understood that many modifications and variations may be made in carrying out the invention, without departing from the spirit and scope thereof. as previously indicated,only the general principles of the apparatus have been outlined, because it is well' within the power of anyone skilled in thisart to construct a machine or to apply this type of apparatus to a given type of machine.- r

Having thus described the invention, what I claim as new and desire'to secure by Letters Patent of the United States is:

1. In the art of making cone-shaped cups This from flexiblesheet material, the step prior 'to the completion of the cup forming operation which comprises forming a predetermined crease by' the application of a predetermined pressure in that portion of the material from which the apex of the cup is formed.

2. In the art of making cone-shaped cups from flexible sheet material, the step prior to the completion of the cup forming operation which comprises applyingto said sheet material a predetermined pressure which forms a predetermined crease in a portion thereofadjacent the apex of the cup, and winding said material around said creased portion in the formation of the cup.

3. Inthe art 'of making cone-shaped paper cups, the step which comprises feeding a continuous sheet .of pap'erfrom a roll and forming paper'cups on the end'of saidsheet of paper.

and prior to the formation of said cups applying a predetermined pressure to-said strip of paper sufncie'nt to form a predetermined crease therein at the apex of the cup.

Q. In the art ofmaking cone-shaped paper cups, the step which comprises-applying a predetermined pressure to the material from which said cups are-formed, suflicient to produce a plurality of creases extending in opposite directions and intersecting at the apex of each cup, and winding said paper around said creased portion.

5. .An apparatus for forming cone-shaped cups comprising, the combination of; a cone-shaped forming mandrel, means for supplying a material to said mandrel to be wound thereon and formed into a cup, and means for applying a predetermined pressure to said material at the point which is to form the apex of the cup prior to the completion of the winding operation;

. 6, In an apparatus of the character described, the combination of, a forming mandrel for making cone-shaped paper cups, means for supplying a material to said mandrel to be wound into a cup. and mechanical means associated .with said'mandrel adapted to exert a predetermined pressure. during the winding operation at the '7 In'an apparatus of the character described, the ,.combination of, a conical forming mandrel,

' point of the material which is to form the apex of the cup.

means for supplying a material to said mandrel to be wound into acup, and means including a sharp point in.the apex of'said mandrel adapted to move out-during the forming operation and 4 of the material which is toform the apex of the exert a predetermined pressure against that part 

